Non-volatile memory devices, such as flash memory devices, may be provided in a NOR-type configuration or a NAND-type configuration. By way of example, NOR-type flash memory devices may provide relatively fast random access, while NAND-type flash memory devices may provide relatively low cost and/or relatively high integration. NOR-type flash memory devices may thus be used for code memory storage, while NAND-type flash memory devices may be used for mass memory storage.
NAND-type nonvolatile semiconductor memory devices are discussed, for example, in U.S. Pat. No. 7,079,437 to Hasama et al. entitled “Nonvolatile Semiconductor Memory Device Having Configuration Of NAND Strings With Dummy Memory Cells Adjacent To Select Transistors.” More particularly, Hasama et al. discusses a nonvolatile semiconductor memory device having a plurality of electrically rewritable nonvolatile memory cells connected in series together. A select gate transistor is connected in series with the serial combination of memory cells, and the memory cell which is located adjacent to the select gate transistor is a dummy cell which is not used for data storage. During a data erase operation, a same bias voltage that that is applied to the other memory cells is also applied to the dummy cell.
Notwithstanding known nonvolatile memory devices, there continues to exist a need in the art for structures and methods providing more highly integrated memory devices.